The placement of half a dozen nuclear reactors together at the Koodankulam complex in Tamil Nadu is raising concern in the state, though the Govt says there is nothing to worry.

The placement of half a dozen powerful nuclear reactors together at the Koodankulam complex in Tamil Nadu is raising concern in the state, though the government says there is nothing to worry.

Questions are being asked as to what would happen to the spent fuel emerging from the plant, located in Tirunelveli district, about 1,000 km south of Chennai.

The fears have been raised by a spectrum of people from MV Ramana of the Centre for Interdisciplinary Studies on Environment and Development to fishermen.

In a memorandum to the Tamil Nadu Pollution Control Board (TNPCB), Ramana said that the Environmental Impact Assessment (EIA) report on the third to the sixth reactors at Koodankulam "does not mention what is to happen to the spent fuel."

It neither evaluates the potential environmental impacts of just storing this spent fuel while it is cooling, he added. The TNPCB has to approve the project before it can go on stream.

India's Department of Atomic Energy (DAE) plans to place six Russia-made VVER 1,000 MWe reactors in Koodankulam. The department says that no clearance is required for the first two reactors, as those projects were started before 1989 when environmental clearance was not mandatory.

Spent fuel is the radioactive fuel taken out of the reactor. Experts said once all six reactors operate, there would be at last 660 tonnes of spent fuel in the complex at any point of time.

The project director for Koodankulam, SK Agarwal of Nuclear Power Corp of India Ltd (NPCIL), told IANS: "This spent fuel is under hot condition and has to be stored under water at (the) project site for five to 10 years, which is the cooling-down period before it can be transported.

"As per the DAE policy, we follow the 'closed cycle', which means that the spent fuel is reprocessed in (a) reprocessing plant, and the useful material, ie, plutonium, is taken out, which can be used for further energy production.

"The waste, after reprocessing, which is left out is a very small quantity which is vitrified and deposited in repository in a safe manner."

But Ramana said the reactors would have a "disastrous effect" on "thousands of people living nearby and the delicate marine ecological system, comprising over 36,000 species."

The Tamil Nadu and Pondicherry Fisher Peoples' Federation representative, Gilbert Rodrigo, told IANS: "India has experience of 500 MW reactors. When 1,000 MW reactors have not even begun generation, and we don't for sure know how they will behave, what is the need to have six such reactors in one site?"

Ramana expressed concern about the reliability of the control rod mechanism of VVER 1,000 reactors. He also pointed out "deficiencies" in the EIA, which was carried out by the National Environment Engineering Research Institute (NEERI), based in Nagpur.

"EIA does not consider the possibility of severe accidents," Ramana said. "One standard accident scenario whose impact should have been studied as part of EIA is that of a 'Loss of Coolant Accident' coupled with a loss of electric power (station blackout)."

But this has not been done, according to Ramana's memo to the TNPCB.

"Another dangerous combination could be a 'Loss of Coolant Accident' and a failure of the Emergency Core Cooling system," according to Ramana. He felt that this possibility should also have been considered in EIA.

"The EIA has not considered at all the possibility of a 'beyond design basis' accident of a reactor that could lead to a massive release of radioactivity to the environment," Ramana added.

The radioactive chemicals that would be released to the atmosphere in case of an accident would include strontium and cesium-137. Strontium enters the food chain, while cesium-137 changes to the poisonous barium-137, Ramana pointed out.

"Contamination could reach as far as 400 km from the reactor site", he added. That radius includes the temple town of Madurai and parts of Kerala.

The water let out into the sea by the Koodankulam nuclear power station will be 13 times hotter than what the Kalpakkam reactors let out, according to Ramana.

Environmentalists are demanding that the EIA report be translated into Tamil so that all local residents can understand the implications of having the reactor complex in their neighborhood.

Activists are also demanding resumption of public hearings on the issue.